SOLUTION: What is the solution of the equation? Eliminate any extraneous solutions. sqrt (3x+28)-8=x

Algebra ->  Test -> SOLUTION: What is the solution of the equation? Eliminate any extraneous solutions. sqrt (3x+28)-8=x       Log On


   

Question 841722: What is the solution of the equation? Eliminate any extraneous solutions. sqrt (3x+28)-8=x

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt (3x+28)-8=x
(3x+28)=(8+x)^2
(3x+28)=64+16x+x^2
x^2+13x+36=0
(x+4)*(x+9)=0
x=-4 x=-9
Try them in the original equation
sqrt (-12+28)-8=-4
sqrt(16)-8=-4
4-8=-4
sqrt (-27+28)-8=-9
sqrt(1)-8==9
-1-8=-9
x=-9
-9 is an extraneous root but I am not sure why
x=-4